Can lice transmit diseases? Lice generally do not transmit diseases, especially head lice, which are the most common type found on humans. However, body lice (a different species that lives on clothing rather than on the scalp) can stages of lice diseases in rare cases. Body lice have been known to spread illnesses such as trench fever, relapsing fever, and epidemic typhus in conditions where hygiene is poor, and people are in close contact, such as in crowded or unsanitary environments.
Head lice do not carry these diseases, but they can cause secondary infections if excessive scratching leads to open sores on the scalp. These sores can become infected by bacteria, requiring medical treatment. The main health concerns with lice are discomfort, irritation, and potential for skin infections from scratching, rather than the transmission of serious diseases.